ASoC: SOF: Intel: SKL: Fix device description

Add missing ops_free callback for SKL/KBL platforms.

Fixes: 52d7939d

 ("ASoC: SOF: Intel: add ops for SKL/KBL")

Signed-off-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com>
Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Reviewed-by: Bard Liao <yung-chuan.liao@linux.intel.com>
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@linux.intel.com>
Link: https://lore.kernel.org/r/20230307093914.25409-4-peter.ujfalusi@linux.intel.com
Signed-off-by: Mark Brown <broonie@kernel.org>